Need help with Visability Expression

system_migrated

I have a report where the user is presented with a List box parmater to choose which tables they want to see. Using that, I am trying to configure the expression in the Visability feature but can not figure out how to do it. I know there are other threads that refer to a report I can download, but I can not open those. What is the proper syntax for the expression if I am trying to hide it.
thanks
doug